[#478] Change assertions in MultipleContextTest

I'm not sure why but it fails with the latest JDK on CI
otherwise.

Author: DavideD

hibernate-reactive-core/src/test/java/org/hibernate/reactive/MultipleContextTest.java

@@ -60,7 +60,7 @@ public void testPersistWithStage(TestContext testContext) throws Exception {
 						testContext.assertNotNull( e );
 						testContext.assertEquals( CompletionException.class, e.getClass() );
 						testContext.assertEquals( IllegalStateException.class, e.getCause().getClass() );
-						testContext.assertTrue( e.getMessage().contains( ERROR_MESSAGE ) );
+						testContext.assertEquals( ERROR_MESSAGE, e.getMessage() );
 						return null;
 					} ) )
 		);
@@ -85,7 +85,7 @@ public void testFindWithStage(TestContext testContext) throws Exception {
 						 testContext.assertNotNull( e );
 						 testContext.assertEquals( CompletionException.class, e.getClass() );
 						 testContext.assertEquals( IllegalStateException.class, e.getCause().getClass() );
-						 testContext.assertTrue( e.getMessage().contains( ERROR_MESSAGE ) );
+						 testContext.assertEquals( ERROR_MESSAGE, e.getMessage() );
 						 return null;
 					 } ) )
 		);
@@ -108,7 +108,7 @@ public void testOnPersistWithMutiny(TestContext testContext) throws Exception {
 					 .onItem().invoke( v -> testContext.fail( "We were expecting an exception" ) )
 					 .onFailure().recoverWithUni( e -> {
 						 testContext.assertEquals( IllegalStateException.class, e.getClass() );
-						 testContext.assertTrue( e.getMessage().contains( ERROR_MESSAGE ) );
+						 testContext.assertEquals( ERROR_MESSAGE, e.getMessage() );
 						 return Uni.createFrom().voidItem();
 					 } ) )
 		);
@@ -131,7 +131,7 @@ public void testFindWithMutiny(TestContext testContext) throws Exception {
 					 .onItem().invoke( v -> testContext.fail( "We were expecting an exception" ) )
 					 .onFailure().recoverWithUni( e -> {
 						 testContext.assertEquals( IllegalStateException.class, e.getClass() );
-						 testContext.assertTrue( e.getMessage().contains( ERROR_MESSAGE ) );
+						 testContext.assertEquals( ERROR_MESSAGE, e.getMessage() );
 						 return Uni.createFrom().nullItem();
 					 } ) )
 		);